Level 1 vs level 2 charging

[Ronmamacleaf]

I'm getting a lot of mixed messages from my fellow leaders just need clarification.

-Level 2 is more efficient for charging?
-Level 1 uses as much electricity at level 2
-Level 1 charging is harmful for our car.
-Level 2 uses up to 5x more electricity than level 1.

Thank you.

 

[Graffi]

An easy way to think about it is:
L1 gives about 5 miles each hour.
L2 gives about 25 miles each hour (5x as much miles in a given time).
L3 gives about 125 miles each hour (5x as much as L2).

There is a fixed amount of loss or usage for a given time period during charging regardless of L1, L2, or L3, therefore the faster you can charge the less loss there is. Therefore L3 is more efficient than L2, L2 is more efficient than L1.

Hopes this helps.

 

[Ronmamacleaf]

But its stated not to do to many quick charges.

 

[RonDawg]

But its stated not to do to many quick charges.

You do want to limit the frequency of your QC sessions, and QC was never intended as a primary charging source, only as an occasional "range extender."

L2/240 volt does NOT use up 5x the electricity of L1. The Leaf battery is only 24 kWH and you can"t cram anymore into it, no different than if you are trying to fill a bucket with a garden hose or a fire hose. L2 is more efficient because the higher voltages mean less losses (you utilize more of the actual electricity that you are drawing), and of course charges much faster than L1/120 volt. But if your daily range requirements are low, and you have a dedicated 120 volt circuit in your parking area, you can get away with just L1 charging. I was able to survive on that for 9 months before finally getting a dedicated L2 unit installed.

L1 is absolutely NOT harmful to the car. The reason Nissan does not recommend it is because besides being slow, many people do not have a dedicated 120 volt outlet in their garage (meaning it's not shared with anything else especially high wattage appliances like fridges and power tools) or else it's in poor condition. A few people here have had FIRES as a result of using L1 charging with a circuit that was not adequately prepared/inadequately installed.

 

[cwerdna]

-Level 2 is more efficient for charging?

Yes.

-Level 1 uses as much electricity at level 2

No. See above.

-Level 1 charging is harmful for our car.

No.

-Level 2 uses up to 5x more electricity than level 1.

Not sure what you mean.. in a given amount of time, yes, more energy will come out of the wall. If you charge at 120 volts w/the stock L1 EVSE, in 1 hour, 1.4 kWh would've come out of the wall. If you had a 240 volt L2 30 amp EVSE and 6.x kW OBC, then ~6.6 kWh would've come out of the wall. But, in the latter case, less energy would've been thrown away and you'd reach full MUCH faster.

At home, you're always going to be billed by kWh. To go from point A to B state of charge, fewer kWh need to come out of the wall when charging efficiency is higher (e.g. level 2).

A few places might also have demand charges (in kW) for residential plans, but those seem to be rare.

There were some studies on charging efficiency at http://www.mynissanleaf.com/viewtopic.php?t=19899.

 

[Sondy132001]

-Level 2 is more efficient for charging?

Yes.

-Level 1 uses as much electricity at level 2

No. See above.

-Level 1 charging is harmful for our car.

No.

-Level 2 uses up to 5x more electricity than level 1.

Not sure what you mean.. in a given amount of time, yes, more energy will come out of the wall. If you charge at 120 volts w/the stock L1 EVSE, in 1 hour, 1.4 kWh would've come out of the wall. If you had a 240 volt L2 30 amp EVSE and 6.x kW OBC, then ~6.6 kWh would've come out of the wall. But, in the latter case, less energy would've been thrown away and you'd reach full MUCH faster.

At home, you're always going to be billed by kWh. To go from point A to B state of charge, fewer kWh need to come out of the wall when charging efficiency is higher (e.g. level 2).

A few places might also have demand charges (in kW) for residential plans, but those seem to be rare.

There were some studies on charging efficiency at http://www.mynissanleaf.com/viewtopic.php?t=19899.

This (bolded) if you charge at 12 hours plus from Level 1 (trickle charge), like me, from 6pm when I get home to 7:30am when I leave for work, the prices are all stage differently, so I pay more than say the person who has Level 2 and can start their charging at midnight (which is the cheapest kW in my city) and be done by 4-5am fully charged. So Level 2 is Ideal.

 

[Valdemar]

A coolant pump runs continuously while charging, as L1 is 2.5 times longer than L2 charging on L1 almost exclusively will surely cause some extra wear to it.

 

[LeftieBiker]

An easy way to think about it is:
L1 gives about 5 miles each hour.

That's best case, assuming a full range of 100 miles. Why do people keep transposing two simple numbers? It's 5% charge added per hour with L-1, or about 4 miles of range. Not vice versa.

 

[jstack6]

Most people can't measure the difference in efficiency between any of the levels. It is a FACT that L1 takes longer but if your in a hurry you may know of a local L2 or L3 at a dealer that is even free.

If you pay demand charges a fast L2 can cost more on your electric bill. Always try to charge Off Peak at night when rates can be lower if your on a Time Of Day rate. In NYS I saw the public charging is very costly at 55 cents a kWh. Home is about 15 cents kWh.

So a lot to consider so figure out what works for you. L1 and L2 will not harm the battery. Heat is the biggest issue and NYS is not real hot. L3 can make some heat so try not to use that more than 1 time a day if you have other choices.

 

[LeftieBiker]

Heat is the biggest issue and NYS is not real hot.

For a Leaf battery, even Upstate NY is indeed often "real hot." The weekend I leased my 2013 it was in the Nineties, and we had 13 or more days above 90F that Summer. This Summer we've had about six 90F or hotter days, with more expected. You only need days in the 80s, with warm nights, to make battery heat an issue.

 

[dgpcolorado]

Most people can't measure the difference in efficiency between any of the levels. It is a FACT that L1 takes longer but if your in a hurry you may know of a local L2 or L3 at a dealer that is even free...

Just because most people aren't set up to "measure the difference in efficiency" doesn't mean that it isn't real and substantial. I get about 88% efficiency with 3.8 kW charging; it would be somewhat higher with 6.6 kW charging. Level 1 — 1.4 kw — charging has been measured by others at about 75% efficient.

The other big advantage of L2 over L1 is that preheating is much more effective when charging at Level 2. Whether that is important would depend on where the OP lives; it's a big deal in the snowbelt.